Display snooping

ABSTRACT

Circuitry that may be placed in a communication pathway between a host computer and a second display device external to the host computer. One example provides an interface circuit that receives communication signals from a host computer. These signals may be AUX signals sent over a DisplayPort or Thunderbolt connection. The interface circuit may pass these signals to the second display device directly, it may modify them before passing them on, it may ignore them, or the interface circuit may pass them to a processor associated with the second display device.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional patent application Ser. No. 61/446,027, filed Feb. 23, 2011, which is hereby incorporated by reference.

BACKGROUND

Computing environments continue to evolve. One of the latest evolutionary steps is the use of more than one display screen to view data generated by a computer system. For example, a computer designer may use one display to show a schematic of a portion of an electronic device and another display to show a layout of that portion of the electronic device.

The inclusion of multiple displays is driven by many factors. For example, computing tasks are becoming more complicated. These tasks are being handled by more powerful programs and computing resources, which are able to provide multiple graphics images. Also, the costs of such displays and associated hardware have been reducing as the quality has been increasing. Moreover, users are becoming more skilled and are able to handle more data.

These displays may be of various types. For example, they may be dedicated displays that are separate from computing devices. They may also be displays that are integrated into a computing device, such as a desktop, all-in-one computer, laptop, netbook, tablet, ultrabook, or other such device.

It is often fairly straight-forward to use a dedicated display as a second display. Dedicated displays are configured to accept not only video information from an external source, but control signals as well. These control signals may include signals to adjust brightness, audio levels, resolution, and others.

Display panels that are integrated with, or are connected to, other devices may not be so flexible, however. These displays may be configured to communicate these signals with the computing devices of which they are a part. They may not be configured to accept signals from external computing devices. As such, these displays may not be as suitable for use as a second display device.

Accordingly, what is needed are circuits, methods, and apparatus that provide displays that may be used as secondary display devices.

SUMMARY

Accordingly, embodiments of the present invention may provide circuits, methods, and apparatus that provide displays that may be used as secondary display devices.

An illustrative embodiment of the present invention provides a circuit that may be placed in a communication pathway between a host computer and a second display device external to the host computer. The host computer or device may be a desktop computer, all-in-one computer, laptop, netbook, or tablet computer, ultrabook, or other computing device. The second display may be a desktop, all-in-one computer, laptop, netbook, or tablet computer, ultrabook, or other computing device. This circuit may be an interface circuit referred to as a native host interface circuit. This interface circuit may be located in, or associated with, the second display device, though in other embodiments of the present invention, some or all of the interface circuit may be located in the host computer.

An illustrative embodiment of the present invention provides an interface circuit that receives communication signals from a host computer. These signals may be auxiliary or AUX signals sent over a DisplayPort or Thunderbolt connection. These signals may be sent over a point-to-point connection from the host computer to the interface circuit. These signals may further be sent over a point-to-point connection from the interface circuit to the panel. Return signals may be provided over point-to-point signals from the panel to the interface circuit, then from the interface circuit to the host computer. In other embodiments of the present invention, these signals may travel through several point-to-point hops before reaching their destination. For example, one or more intermediate devices, such as hard drives, other display devices, or other devices, may be inserted between a host device and a second display.

An illustrative embodiment of the present invention provides an interface circuit that may receive communication signals from a host computer and pass them to a display panel in various ways. For example, some communication signals may be received from a host computer and then provided to the display panel without alteration. Other communication signals may be modified or altered before being passed to the display panel. Still other signals may be passed to a processor in, or associated with, the display panel. The interface circuit may then receive signals from the processor, which it may then pass to the display panel. In other examples, the processor may instead communicate with the display directly. For example, the processor may communicate with the display panel using Inter-Integrated Circuit (I2C) or other appropriate signaling. Still other signals may be ignored by the interface circuit. For example, various panels may be responsive to one or two or more signals for a particular action. A host computer may send each of these two or more signals to the interface circuit. The interface circuit may then pass on only the signal understood by the display panel and it may ignore the others.

These various techniques may be applied to communication signals conveying various types of information. For example, these techniques may be applied to signals sent to adjust display panels settings such as audio level, screen resolution, contrast, brightness, and others. These techniques may be applied to other types of signals, for example, signals provided by the panel indicating a present state of these settings, security, identification, and authorization signals.

Various embodiments of the present invention may incorporate one or more of these and the other features described herein. A better understanding of the nature and advantages of the present invention may be gained by reference to the following detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a computer system that may be improved by the incorporation of embodiments of the present invention;

FIG. 2 illustrates a block diagram of a portion of a computer device according to an embodiment of the present invention;

FIG. 3 illustrates a path for video signals in a portion of a computer device according to an embodiment of the present invention;

FIG. 4 illustrates a signal path for an interface circuit to receive auxiliary data according to an embodiment of the present invention;

FIG. 5 illustrates a signal path for an interface circuit to provide auxiliary data to a display panel according to an embodiment of the present invention;

FIG. 6 illustrates a signal path for an interface circuit to receive auxiliary data from a display according to an embodiment of the present invention;

FIG. 7 illustrates an interface circuit providing data to a host device according to an embodiment of the present invention; and

FIG. 8 illustrates a signal path for auxiliary data that includes a CPU and memory according to an embodiment of the present invention.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 illustrates a computer system that may be improved by the incorporation of embodiments of the present invention. This computer system may be used to provide a user with a computer system having two displays. While two devices that include a display are shown in this figure, embodiments of the present invention may be used in computer system having three or more devices having displays. This figure, as with the other included figures, is shown for illustrative purposes and does not limit either the possible embodiments of the present invention or the claims. It should also be noted that while embodiments of the present invention are well-suited to Thunderbolt systems that convey DisplayPort AUX and video data, other embodiments of the present invention may be used to convey other signals consistent with other standard and proprietary protocols, such as High-Definition Multimedia Interface (HDMI) signals, or other signals consistent with other protocols that may be currently under development, or may be developed in the future.

In this example, host computer 110 may be in communication with second display device 130 over cable 120. Host computer or device 110 may be a desktop computer, all-in-one computer, laptop, netbook, or tablet computer, ultrabook, or other computing device. Second display device 130 may be a desktop, all-in-one computer, laptop, netbook, or tablet computer, ultrabook, or other computing device. In this particular example, host computer 110 is a laptop computer having display 112, while second display device 130 is an all-in-one computer that includes display 132, keyboard 134, and mouse 136.

Again, host computer 110 may be in communication with second display 130 over cable 120. Cable 120 may be a DisplayPort cable, Thunderbolt cable, or other appropriate cable. Cable 120 may be used by host computer 110 to provide video signals to second display 130. Cable 120 may also be used by host computer 110 to provide communication signals to, and receive communication signals from, second display 130. Examples of how this may be done are shown in the following figures.

FIG. 2 illustrates a block diagram of a portion of a computer device according to an embodiment of the present invention. This computer device may be used as, or associated with, a second display, such as second display 130 in FIG. 1, or as second displays in other embodiments of the present invention.

This figure includes connector receptacle 210, switch 220, DisplayPort output 230, display panel 240, interface circuit 250, and CPU and memory 260. Connector receptacle 210 may be a DisplayPort or Thunderbolt compatible connector receptacle. Connector receptacle 210 may receive and provide DisplayPort signals 212 over a thunderbolt connection. Connector receptacle 210 may provide DisplayPort 212 signals to switch 220. DisplayPort signals 212 may include auxiliary or AUX signals 214 and video signals 216. When both AUX signals 214 and video signals 216 are present between connector 210 and switch 220, the signals may be sent together on a common electrical connection, or they may be sent in parallel on two electrical connections, as shown in the figure. Switch 220 may provide auxiliary signals 224 and 222 to interface circuit 250 and DisplayPort output 230. Switch 220 may also provide video signals 226 to DisplayPort output 230. DisplayPort output 230 may provide auxiliary signals 232 and video signals 234 to display panel 240. Interface circuit 250 may provide auxiliary signals 252 to CPU and memory 260. CPU and memory 260 may provide signals, such as I2C signals 262, to display panel 240.

Again, a host computer or device may provide video signals to display panel 240. An example of this is shown in the following figure.

FIG. 3 illustrates a path for video signals in a portion of a computer device according to an embodiment of the present invention. Video data may be received over DisplayPort connection 212 by connector receptacle 210. Video signal 216 may be provided by connector receptacle 210 to switch 220. Switch 220 may provide video signal 226 to DisplayPort output 230. DisplayPort output 230 may provide video signals 234 to display panel 240. Display panel 240 may then display video data.

The video signal 226 received by DisplayPort output 230 may be arranged as DisplayPort data. DisplayPort output 230 may remove excess data and provide a video signal 234 to display panel 240. For example, video data to be displayed may be removed from DisplayPort, Thunderbolt, or other types of packets by DisplayPort output 230 or other associated circuitry.

In this example, switch 220 may switch video data to display panel 240 via DisplayPort output 230. Switch 220 may also provide AUX data to interface circuit 250. An example is shown in the following figure.

FIG. 4 illustrates a signal path for an interface circuit to receive auxiliary data according to an embodiment of the present invention. This auxiliary data may be received as part of DisplayPort signal 212 by connector receptacle 210. Auxiliary data 214 may be received by switch 220. Switch 220 may provide auxiliary data 224 to interface circuit 250.

This auxiliary data may be various types of data. For example, auxiliary data 214 and 224 may include signals to adjust display panels settings such as audio level, screen resolution, contrast, brightness, and others. These signals may be other types of signals, for example, signals provided by the panel indicating a present state of these settings, security, identification, and authorization signals.

Once interface circuit 250 receives auxiliary data 224, it may handle this data in one of a number of ways. For example, interface circuit 250 may ignore this auxiliary data. Specifically, various display panels 240 may understand one of a number of versions of a command. A host device may send each of these versions to interface circuit 250. Interface circuit 250 may then forward only the appropriate version to display panel 240. In other examples, interface circuit 250 may alter, substitute, or pass auxiliary data to display panel 240 without modification. An example of this is shown in the following figure.

FIG. 5 illustrates a signal path for an interface circuit to provide auxiliary data to a display panel according to an embodiment of the present invention. In this example, interface circuit 250 may provide auxiliary data 224 to switch 220. Switch 220 may provide auxiliary data 222 to DisplayPort output 230, which may in turn provide auxiliary data 232 to display panel 240.

In various embodiments, this auxiliary data may be a request for information from display panel 240. In such a case, display panel 240 may provide auxiliary data back to the host device. This auxiliary data may be routed through interface circuit 250. An example is shown in the following figure.

FIG. 6 illustrates a signal path for an interface circuit to receive auxiliary data from a display according to an embodiment of the present invention. Display panel 240 may provide auxiliary data 232 to DisplayPort output 230. DisplayPort output 230 may provide auxiliary data 222 to switch 220. Switch 220 may, in turn, provide auxiliary data 224 to interface circuit 250. Once interface circuit 250 receives the auxiliary data, it may in turn pass this auxiliary data to the host device. An example is shown in the following figure.

FIG. 7 illustrates an interface circuit providing auxiliary data to a host device according to an embodiment of the present invention. Interface circuit 250 may provide auxiliary data 224 to switch 220. Switch 220 may provide auxiliary data 214 to connector receptacle 210. Connector receptacle 210 may turn provide this auxiliary data 214 over DisplayPort path 212 to a host device.

In various embodiments of the present invention, interface circuit 250 may not be capable of providing control signals for certain functions defined by auxiliary data to display panel 240. An example of this may be audio control signals. That is, interface circuit 250 may not have a mechanism to control an audio setting in or associated with display panel 240. In such a situation, interface circuit 250 may provide commands to CPU and memory 260, which may then provide audio control signals to display panel 240, or circuitry associated with display panel 240. An example of this is shown in the following figure.

FIG. 8 illustrates a signal path for auxiliary data that includes a CPU and memory according to an embodiment of the present invention. In this example, DisplayPort data 212 may be received at connector receptacle 210. Connector receptacle 210 may provide auxiliary data 214 to switch 220. As before, switch 220 may provide auxiliary data 224 to interface circuit 250. Interface circuit 250 may in turn provide auxiliary data 252 to CPU and memory 260. CPU and memory 260 may then process these instructions to generate processed instructions. CPU and memory 260 may then provide processed instructions 262 or other data to display panel 240. This may be done as auxiliary data, or as other types of data, such as I2C data 262. In other embodiments of the present invention, CPU and memory 260 may return AUX data 252 back to interface circuit 250. Interface circuit may then provide the AUX data back to the display panel or host device, as shown above.

The above description of embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Thus, it will be appreciated that the invention is intended to cover all modifications and equivalents within the scope of the following claims. 

1. A method of communicating with a remote host computer comprising: receiving video and communication information from the remote host computer using a switch; providing the video information to a panel with the switch; receiving the communication information from the switch with an interface circuit; and providing the communication information to the panel with the interface circuit.
 2. The method of claim 1 wherein the switch, interface circuit, and panel are housed in a computing device.
 3. The method of claim 2 wherein the computing device is a laptop computer.
 4. The method of claim 2 wherein the computing device is an all-in-one computer.
 5. The method of claim 2 further comprising: receiving response communication information from the panel with the interface circuit; providing the response communication information to the switch using the interface circuit; and providing the response communication to the host computer using the switch.
 6. The method of claim 2 wherein the video and communication information is DisplayPort information.
 7. The method of claim 6 wherein the DisplayPort information is provided over a Thunderbolt connection.
 8. The method of claim 2 wherein the communication information comprises a command to set a resolution.
 9. A method of communicating with a remote host computer comprising: receiving video and communication information from the remote host computer using a switch; providing the video information to a panel with the switch; receiving the communication information from the switch with an interface circuit; providing the communication information to a central processing unit; and providing processed communication information to the panel from the central processing unit.
 10. The method of claim 9 wherein the switch, interface circuit, and panel are housed in a computing device.
 11. The method of claim 10 wherein the computing device is a laptop computer.
 12. The method of claim 10 wherein the computing device is an all-in-one computer.
 13. The method of claim 10 wherein the video and communication information is DisplayPort information.
 14. The method of claim 13 wherein the DisplayPort information is provided over a Thunderbolt connection.
 15. The method of claim 10 wherein the communication information comprises a command to set an audio volume.
 16. A computing device comprising: a connector receptacle; a switch coupled to the connector receptacle; an interface circuit coupled to the switch; and a panel coupled to the switch, wherein video and communication information is received at the connector receptacle, video information is provided by the switch to the panel, and communication information is provided by the switch to the interface circuit.
 17. The computing device of claim 16 further comprising: an output circuit coupled between the switch and the panel, wherein the output circuit receives video information and provides processed video information to the panel.
 18. The computing device of claim 16 wherein the interface circuit is coupled to provide communication information to the panel.
 19. The computing device of claim 16 wherein the interface circuit is coupled to the output circuit to provide communication information to the panel.
 20. The computing device of claim 16 wherein the interface circuit is coupled to provide communication information a processing circuit.
 21. The computing device of claim 20 wherein the processor is coupled to provide processed communication information to the interface circuit.
 22. The computing device of claim 20 wherein the processor is coupled to provide processed communication information to the panel.
 23. The computing device of claim 16 wherein the video and communication information is DisplayPort information.
 24. The computing device of claim 23 wherein the DisplayPort information is sent over a Thunderbolt channel. 